Hey OM Eb;
There are TWO ways to access files in /boot .
ONE is while you are using the system itself, in which case you must access them via "super user" (also known as "root" user) and that can be accomplished by invoking:
sudo <followed-by-the-command-you-want-to-execute-&-a-return>
TWO is the way Jason uses in his video referred to in STEP 2 of my Headless and Wireless from the Get Go instructions. In that case you are NOT using the system in question at all (i.e. neither directly or indirectly). INSTEAD the partitions are mounted on a host computer (usually with an sd-card to USB converter). In that case you are mounting them as the host computer's user login; AND you wouldn't be getting the error you describe !!
I hope this helps clear up some of the confusion.
es vy 73 om de "baab" w9ya